org.apache.hadoop.mapred.lib
Class IdentityMapper

java.lang.Object
  org.apache.hadoop.mapred.MapReduceBase
      org.apache.hadoop.mapred.lib.IdentityMapper

All Implemented Interfaces:

Closeable, JobConfigurable, Mapper

public class IdentityMapper
extends MapReduceBase
implements Mapper

Implements the identity function, mapping inputs directly to outputs.

Constructor Summary

IdentityMapper()

Method Summary

void	map(WritableComparable key, Writable val, OutputCollector output, Reporter reporter) The identify function.

Methods inherited from class org.apache.hadoop.mapred.MapReduceBase

close, configure

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.hadoop.mapred.JobConfigurable

configure

Methods inherited from interface org.apache.hadoop.io.Closeable

close

Constructor Detail

IdentityMapper

public IdentityMapper()

Method Detail

map

public void map(WritableComparable key,
                Writable val,
                OutputCollector output,
                Reporter reporter)
         throws IOException

The identify function. Input key/value pair is written directly to output.

Specified by:

map in interface Mapper

Parameters:

key - the key

val - the values

output - collects mapped keys and values

Throws:

IOException